Portable sander tool



July 4, 1933. c. D, WELCH PORTABLE SANDER TOOL Filed June 18, 1930 3Sheets-Sheet 1 gmma Georgefl. [U916]? gm K. W

July 4, D H' 1,916,543

PORTABLE SANDER TOOL Filed June 18, 1930 s Shets-Sheet 2 eorgeD. [U616]?gnwntoz Patented July 4, 1933 UNITED STATES PATENT OFFICE GEORGE D.WELCH, OF HOQUIAM, WASHINGTON PORTABLE SANDER TOOL Application filedJune 18,

10 or polishing'flat or curved surfaces generally.

U My general object is to provide a small, light, and easily handledtool, which may be moved about over a surface, even of considerablearea,and so arranged that the workman may engage the inside of the flower runof the fiexible sander belt'with his hand whenever he wishes, to bringthe sander belt into contact at the selected' spot with the surfaceofthe Work. '1

' It is an object to provide means whereby such a sander may beheld withthe belt normally out of contact with'the work, but with meanspermitting yielding of the belt under pressure of the workmans hand, topermit its deflection into contact with the work.

" It is afurther object to providesuch a tool wherein the sander belt iscarried upon rollers from which it may be very simply re movedover oneend of the rollers. It is also an object to provide a means whereby theaccidental removal of the sander belt from the rollers is prevented.

It is a further object to provide means to exactly align the severalrollers, both the 5 belt-carrying rollers, the tightener roller, and

a pressure roller.

Other objects, and especially such as relate to the mechanical detailsof such a structure, will be ascertainable from a study of the followingspecification, of the attached drawings, which show my invention in aform at present preferred by me, and of the claims which terminate thespecification.

Figure 1 is a plan view of the tool forming my invention, a part of thesander belt being broken away.

Figure 2 is a side elevation of the machine from the forward or outerside, that is the side from which the sander belt is removed.

Figure 3 is an end elevation of my device on a large scale, taken fromthe right, as seen in Figures 1 and 2.

Figure dis a transverse sect on through my device on the line 4-4 ofFigure 2.

Figure 5-is a rear side elevation of one end of my tool.

1930., Serial in. 461,967. V

Figure 6 is ofFigure 5. 7 t

Figure 7 is a detail section on the line'-7-7 ofFi uieQ. ,1 v v Figure8is a detail persp ctiveTviewfof the mounting for oneof the rollers. j VEssentially, my device comprises an endless sander belt 9' passingaboutrollers l, 2, 3 and 4, which are held ina frar'ne 5 and one oftheserollers, as the rollei fhi's-mountd to yield, as for iiistance, agai11taspriiigfito, to permit defle'tion of the loweryi uni of the belttowardsiithe worker to-permit tlie belt to be'slacked off to" sli {it,off the ends of the several roll'e'rs fonreplacen'ient- I A' pressureroller 6 may likewise be provided, bearing upon the outside of thesander belt 3 immediately above the'driving roller, which may be theioller,;,1'. To prevent,,,unequa1 wear of the bcltand a tendency ,toclimb, as if the rollers were crowned, duefto-imperfect alignmentor'parallelism ofthe several rollers, means may be provided at goneend,as will be explained, to align one pair of rollers (for instance therollers 3 andA) with the other pair of rollers, particularly with thedrivingroller 1. I prefer also thatthe entire tool be supported efromthe surface of the work, generally designated at S, upon rollers such asare indicatedat 50 and 51, depending below the frame 5, the frame beinggovernable by any convenient means such as the handle 5:2. The drivemaybe variously arranged, and an integral motor may be employed, or aflexible chain drive, or any suitable means. As typical of a means whichmay be employed, I have shown the'drive shaft 10, on which is mountedthe roller 1, journaled in the bearing 15, in the frame, and asprojecting therebeyond for connection to a suitable source of power.

Of the rollers 1, 2, 3 and at, the roller 1, being the driving roller,should be journaled in the frame 5, and its companion roller 2 of thesame pair is preferably also journalcd in the frame. To the latter end,the frame 5 at each end of the roller 2 may be notched, as indicated at25, to permit a shaft 20, upon which the roller 2 is journaled in thebearings 21 (see Figure 8), the bottom of the notch 25 being enlarged asindicated at 23, to receive the circular extension 24 of a nut 22. Bythese or like means, the shaft '20 is re tained, centered in theenlargement 23, yet upon slacking off the nuts 22 (the sander belt adetail section oii'the line 6,6

having first been removed) the roller 2 may easily be slipped from theframe, withdrawing its shaft'QO throughthe slots 25. By such means, itmay be held definitely and precisely in parallelism with the axis of thedriving roller 1.

The roller 3 is paired with the roller 4, and to permit alignment, orthe bringing'of these two rollers into parallelism with the rollers 1and 2, particularly the roller'l, they are carried ,byanti-frictionbearings 32 and leap-on the respective shafts 31 and 41,which shafts are supported from a longituinally' extending lever 7 Thislever is pivoted upon the frame by means of a bolt passingthrou' hears57 and through the end of th leverfi; "Adjustr'nent o'r7'transverseswingingof tlielever '7 is accomplished by means 'su'chfas thedifferential screw 71 (see Figure A portion 72 of slight pitch isthreaded in the frame 5 and a portion 73 of greaterpitch is threaded inthe swinging end of the? 'e'ver"7. Theadjust ment which is fihal ljattained by this screw '71 is held by such means'as the lock nut 7 4. l-Thetwofshafts '31 and flare not each rhceivedfdirectly in the lever 7Only the shaft 31'is so'held, and the shaft 41,carryiin the tightenerroller 4:,is secured in the sw ngingehd of an arm8,'wh1ch is mountedtoswing'oii'theshaft 31. The position of the ar fnf'B is' controlled bymeans of a rod 84 through a lug '58 in the frame 5, and about'fwhich rodthe tightener spring 40 is coiled." It "will be noted that the arm 8 isswung 'free, and the shaft 31 is clamped and held in the lever 7 bymeans of a nut 33, clamping the lever 7 through the intermediary of aspacer collar 38, whereby the nut 33. can force against a shoulder 34 onthe shaf't'31. Adjustment of the lever 7 will adjus't the angularposition of the two shafts 31 and 41, although the shaft 41, with itstightener roller 4, is still free to swing about the axis of the shaft31 by means of its mounting on the arm 8, and the influence of thespring 40 thereon.

It will be noted that the frame 5 is dis posed largely at the rear sideof the tool, although it has an upper member 5 covering substantiallythe top run of the sander belt. The several shafts 10, 20, 31 and 41,are all supported from their rear ends, although the shafts l0 and 20are likewise supported at their forward ends; the shafts 31 and 41 arenot. To support the forward ends of the shafts 10 and 20, there isprovided a forward extension 55 of the frame 5, which extension issupported from the main frame 5 by means of a web 54, which projectsbetween the upper and lower runs of the sander belt 9, but sufficientlyabove the lower run to permit insertion of the workmans handtherebetween to en'gage the belt. The frame is omitted therefore belowthe Web 54;, which is spaced above the lower run of the sander belt.

The wheels 51 are secured directly upon the frame 5 and theexten'siori'55, and the wheel 50 may be mounted in a depending leg 59,and thus supported, the frame may be moved over the surface S until itis brought into position over a spot which is to be sanded, whereuponthe workman, placing a hand between the web54 and the'lower run 90 ofthe sander belt, presses down on the sanderbelt, which causes deflectionof thetighterier'roller e ni es tio'n'to .the spring, 40, tojbring ftliesand'er belt own upon: thework, as has-been indicated in do'ttetl linesin'ri ure'a'. 1

, t. ill b notedih t t roller were are free'at theirlou erprforj ends,and thatthe f mefite sidn tenses njerpr jeet outside of an extensionof'th'ejplane of'the sander belt 9,.sqt11atjth reiS iljojobstructio'n toremoval of he S nder belt other than'the tension on the spring-:4 hid,in the fillustra e sl-lj'flow v i a fiion. h ve; he u I when. it is desred Jto change sander belts, it

is, easilyfpo'sfs ibl e to swing i'the tightener roller I inward fiioughjto' previde'fs'lack iii theflbelt u h, a wi l p rmeate piwe thwheel 51,a"nd thus to bremo'v'ed' without dismounting any part of thesander. This wheelf 51,"while thesande 'isfin operation, serves as 'a,positive means to prevent the sander belt'slippingjoifthe rollers;

To assist the driving roller 1'," I'prefer that pressure 'rolle'r6,'previojusly referred to,'be employed, and this is prefe'rably ofrubber. It is mounted on one end of alever-GO, pivoted upon ears 5'6,projecting upward from the top portion or table 5 The lever 60 isengagedat its end opposite thatwhi'cli'carries the rollerjii by a spring 62coiled about alpin 63, having a stop such as a nut 64. The spring62ejxerts pressure to force the roller 6 down into engagement withthesander belt 9, running between the pressure roller 6 and the drivingroller 1.

It will be noted that the lever 60 is formed in two halves, securedtogether by the bolts 65, and to replace the roller 6, it is only necessary to (lismount' the lever 60 and to remove the bolts 65, whereuponthe two halves of the lever 60 may be separated, the shaft 66 beingreleasable from the anti-friction bearings 67,

to permit the insertion of anew roller.

Such a roller is preferably made of or faced with rubber, and unless itis in exact parallelism with the axis of the roller 1, an excessiveamount of abrasion will occur and the roller will be quicklyworn out. Toexactly align it, therefore, I have provided the bolt 68 received in theear 69 of the frame, which bolt is threaded in the head 63 of the pin63, whereby the same may be adjusted transversely of the tool to attainprecise alignment of the rollers 6 and 1.

Vhat I claim as my invention is:

1. In combination with a sander belt, longitudinally spaced idling anddriving rollers carrying the belt, a frame from which said rollers aresupported, two of the idling rollers at one end of the frame comprisinga pair, means for aligning the idling pair with the driving roller, atthe opposite end, and means for yieldably supporting one roller of thepair to permit its movement towards the driving roller when the sanderbelt is deflected.

2, In combination with a sander belt, longitudinally spaced idling anddriving rollers carrying the belt, a frame from which said rollers aresupported, and capable of being moved over the work, a pressure rollerbearing upon the belt over the driving roller, and means for aligningsaid pressure roller with the driving roller.

3. In combination with a sander belt, longitudinally spaced pairs ofrollers, including a driving roller, carrying said belt, a frame fromwhich the several rollers are supported, a pressure roller engageablewith the sander belt above the driving roller, a lever pivoted upon theframe and carrying the pressure roller, and means for swinging saidlever transversely to bring the axis of the pressure roller intoparallelism with the driving roller.

4. The combination of claim 3, the lever being split and the two halvesremovably secured together to retain the roller.

5. The combination of claim 3, the lever swinging means including avertical headed pin engaging the lever, a spring between the head ofsaid pin and the lever, and a transverse screw threaded in the head ofsaid pin, and swiveled in the frame.

6. In combination with a sander belt, longitudinally spaced pairs ofrollers, including a driving roller, carrying said belt, aframesupporting said rollers, wheels depending below the frame to support thebelt above the work, tightening means permitting movement of one of saidrollers parallel to its axis to allow deflection of the belt intocontact with the work, a front supporting member, a horizontal web ofsaid frame extending between the upper and lower runs of said belt tosupport said front member, said web being out out so as to permit accessto the lower run of the belt by the workmans hand.

7 In combination with a sander belt, longitudinally spaced pairs ofrollers, including a driving roller, carrying said belt, and a frameextending at the rear side of the roll ers, and including a support atthe front side of one pair of rollers only, and substantially within theprojected planes of the belt, and connected to the frame in the rearonly by an integral web extending between the runs of the'belt, one pairof rollers being supported between the front and rear elements of theframe, and a member pivotally mounted on a vertical axis, and supportingthe other pair.

8. In combination with a sander belt, a unitary frame movable over thework, a pair of parallel rollers disposed one above the other, meanssupporting said rollers upon the frame, means for relatively adjustingsaid rollers to lie in a common vertical plane, a second pair of rollersand a support therefor carried by said frame, means for relativelyadjusting the rollers of said second pair upon their support to lie in acommon vertical plane, and independently adjustable means adapted toarrange the roller pairs so that their planes are disposed in parallelspaced relationship, the sander belt being carried by said rollers.

9. In combination with a sander belt, a unitary frame movable over thework, longitudinally spaced rollers supported from said frame andcarrying the belt, said rollers being arranged in pairs at each end ofthe frame, and means to align the rollers at opposite ends, disposed andarranged to align one pair of rollers with the opposite pair.

10. In combination with a. sander belt, longitudinally spaced rollerssupporting said belt to form an upper and a lower run, and a framesupporting said rollers, and comprising three integral parts, the firstbeing a plate extending perpendicular to the rollers at one end thereof,the second being a web extending perpendicular to said first partbetween the runs of the sander belt, the third being a plate supportedby said Web and extending parallel to said first plate over the rollersat one end only of the frame, and substantially within the projectedplanes of the belt.

11. The combination of claim 10 and a plate connected to the frameextending perpendicular to the first-mentioned plate and overlying theupper run of the sander belt.

12. In combination with a sander belt, a

frame, a roller directly supported upon said frame, a lever pivoted uponthe frame upon a vertical axis, a transverse roller-carrying shaftsecured in said lever, means to adjust said lever to bring the shaftinto parallelism with the axis of the frame-supported roller, an armmounted to swing upon said shaft, a second transverse roller-carryingshaft carried by said arm, the belt being carried upon said rollers, andmeans for urging said arm and the roller carried thereby against thebelt to tighten the belt.

Signed at Hoquiam, Grays Harbor County, I/Vashington, this 10th day ofJune, 1930.

GEORGE D. WELCH.

